Nothing is impossible to omnipotence; there is nothing that cannot be healed by its Maker.

Origen, De Principiis III. vi.5

The restoration to unity must not be imagined as a sudden happening. Rather it is to be thought of as gradually effected by stages during the passing of countless ages. Little by little and individually the correction and purification will be accomplished. Some will lead the way and climb to the heights with swifter progress, others following right behind them; yet others wil be far behind. Thus multitudes of individuals and countless orders, who once were enemies, will advance and reconcile themselves to God; and so at length the last enemy will be reached…

Origen, De Principiis III.vi.6

…God acts in dealing with sinners as a physician…the fury of his anger is profitable for the purging of souls. Even that penalty which is said to be imposed by way of fire is understood as applied to assist a sinner to health…